Detections
Analytics
CVE-2020-10932
medium
Description
An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.
References
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04
https://tls.mbed.org/tech-updates/security-advisories
https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-released
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html